A conventional goal structure, for example, soccer goal, consists of a couple of different sizes of bars to assemble as a staircase-cutting device. Those bars, mostly combined through welding, and can stand high-speed striking of the ball. However, it is difficult in storage and transportation due to its large size and fixed shape. It is normally placed in fixed position of the field for the players to practice or the games. The players cannot assemble the goal by themselves in places outside the arena.
Recently, some skills are provided to assemble the goal via removable assembly members of goal. These removable assembly members and their connectors can contribute to minimizing space for storing. Moreover, they are easy to carry, so players can practice outside the field by assembling goal on their own. However, the goal made of removable assembly members and connectors still causes some problems, where the steps of assembling and disassembling are too complicated and time-consuming. Usually, it tends to overturn or dismember due to its lower durability.
FIG. 9 shows a schematic view of a conventional ball holder according to a prior art of the invention. As shown in FIG. 9, supports of ball holder 20 have a specific angle of bending to support the base 30. As the result, supports of ball holder 20 with same bending angle should be made in manufacturing process in advance. The angle of these supports 20 is fixed, and cannot be adjusted. On one hand, the size of base 30 corresponding to these supports 20 should be fixed; otherwise, it cannot be put above the supports. On the other hand, supports 20 with bending angle still increases the complexity of storage and transportation.